Fig. S1.

Overview of analysis flows. (A) Detection of clock-regulated genes in human prefrontal cortex (PFC) via metaanalysis. We first estimated the P values of expression rhythmicity for all of the genes in brain regions BA11 and BA47 independently. Then we combined these P values to meta-P values via AW-Fisher and corrected them into q values. A total of 235 cross-region PFC circadian genes were detected at q < 0.05. (B) Detection of age effect on circadian expression rhythmicity. The work flow was independent from A; i.e., the analysis in B did not rely on any a priori results yielded in A. It is possible that a gene shows expression rhythmicity only in younger individuals but not in older individuals (or could be vice versa). Therefore, if younger subjects were mixed with older subjects (e.g., when all 146 subjects were included as how we did in A), we might be unable to detect the expression rhythmicity of certain genes (see Fig. S4 for such examples).